Jim Aronson Current Research Interests

Research Projects:

• Studies of early hominid fossil site of Hadar (Ethiopia)
• Paleohydrological Studies Using Diagenetic/Hydrothermal Clay Mineral and Zeolites

Paleohydrological Studies Using Diagenetic/Hydrothermal Clay Mineral and Zeolites

In a recent study we have shown that clay mineralogy combined with its oxygen isotopes can provide information about paleohydrological conditions. We used this system to Yucca Mountain, the first potential site as a high-level nuclear waste repository. In the same study, we also analyzed oxygen isotopes of clinoptilolite and found that this mineral has reequilibrated with the modern groundwater. Previous studies also indicate that clinoptiloliteÕs K/Ar date is typically younger than the alteration age. We are in the process of determining the kinetics of oxygen isotope exchange between clinoptilolite and water and Ar loss. Quantification of exchange kinetics may have a potential for paleohydrological reconstructions. We are conducting this research using both oxygen isotope and K/Ar systems of clay minerals and zeolites in controlled experiments and field samples with various ages.

For further information, contact Xiahong Feng or Jim Aronson.